Japan's largest drugmaker Takeda Pharmaceutical is considering a bid for London-listed Shire that could top $40 billion and spark another takeover battle in the deal-hungry pharma industry.
Takeda said on Wednesday it was "at a preliminary and exploratory stage" of considering a bid, sending Shire's shares up as much as 26 percent. They were 17 percent higher at 12:15 GMT, valuing the group at 32.7 billion pounds ($46.3 billion).
Shire sells treatments for rare diseases and attention deficit disorder. Takeda said buying it could create a global biopharmaceutical leader, boosting its position in the United States, oncology, gastrointestinal diseases and neuroscience.
The drugs industry has seen a surge in dealmaking as large players look for promising assets to improve their pipelines.
In recent months, Sanofi beat Novo Nordisk in the race for Belgian biotech company Ablynx, while U.S.-based Celgene bagged cancer specialist Juno Therapeutics.
The prospect of a bid for Shire, 57 percent of whose employees are based in North America, immediately stoked expectations for a takeover battle.
"Takeda publicly saying it is considering an approach for Shire inevitably means that other big pharma players including AbbVie, Novartis, Pfizer et al will equally be running the numbers with a very high likelihood of leading to a competitive M&A multi-bidder situation," said Michael Wegener, managing partner at hedge fund Case Equity Partners, which has a stake in Shire.
Takeda said it had not approached Shire's board. Under UK takeover rules, it has until April 25 to decide whether to make a bid.
Shire said it noted Takeda's statement, and confirmed it had not received an approach.
Shire has been under pressure in the last year, with its shares down 24 percent, due to greater competition from generic drugs and a debt pile that stems from its biggest ever deal, the $32 billion acquisition of Baxalta in 2016.
The company announced in January a plan to split into two separate businesses to boost performance.